The present invention relates to a cassette deck provided in a car stereo, and more particularly to a cassette deck where a tape in the cassette is prevented from becoming entangled.
The cassette deck mounted in an automobile must be designed with regard to specific environmental conditions such as humidity, vibration and dust and to operability of the deck.
Referring to FIG. 7, in a cassette 1, a tape 2 wound on a hub is guided by a guide pin 3a and a guide roller 4a and extends across a pressure pad 8. The tape 1 is further guided by a guide roller 4b and a guide pin 3b and wound on a take-up hub. The cassette 1 is inserted in a cassette deck in a direction shown by an arrow c, so that the tape 2 is set between a pinch roller 6b and a capstan 5a and between a pinch roller 6b and a capstan 5b of the cassette deck. For playing the cassette 1, a head 7 of the cassette deck is moved in a direction a so as to abut the tape 2 against the pressure pad 8. When thus playing the tape 2, or when reeling the tape 2 in a direction shown by an arrow in FIG. 7, the pinch roller 6b is moved toward the capstan 5b to hold the tape therebetween. The tape is driven while thus in contact with the pinch roller 6b and the capstan 5b both of which rotate with the running of the tape 2. When the tape 2 is rewound, that is, reeled in the opposite direction, the tape 2 is held by the pinch roller 6a and the capstan 5a.
In order to retrieve the cassette 1, the head 7 is retracted in a direction b and the cassette is ejected in a direction d.
Some of the cassette decks are provided with a cassette deck detecting switch which is closed upon insertion of the cassette. Thus the cassette deck is operated to play the cassette as soon as the cassette is set.
While the cassette is played, the driver of the automobile may turn on other devices such as a CD player without first taking out the cassette, or the ignition switch is turned off thereby cutting off the power from the battery to the cassette deck. As a result, the cassette is left inserted in the deck.
As shown in FIG. 8, a part of the tape 2 is held between the pinch roller 6b and the capstan 5b, or between the pinch roller 6a and the capstan 5a as the case may be. If the cassette is kept in the cassette deck for too long in such a condition, the tape 2 may adhere on the contacting surface of the pinch roller 6b. Consequently, when the cassette 1 is driven the next time, the tape 2 may be wound on the pinch roller 6b, unabled to be reeled. The tape 2 may otherwise be torn. Moreover, the pinch roller 6b may be deformed by the pressure of the capstan 5b, so that wow and flutter occur until the roller 6b retrieves its normal shape.
In order to prevent such troubles, a key-off release mechanism for retracting the pinch roller to its initial position is provided in some types of the cassette deck, hence preventing the tape from being stuck. However the manufacturing cost of the cassette deck is high.